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Master Math: Elementary School Math by Kristen Gryskevich

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Chapter 2Subtraction Algorithms

Traditional Subtraction

This is the algorithm that you will be familiar with from learning math yourself in elementary school. You subtract from right to left and regroup (borrow) as needed throughout the problem.

Many children struggle to remember to cross off the original number in the next place value when regrouping. This is a very common mistake with children in my classroom. I always tell my students that if you are going to “borrow” something from your neighbor, you need to make sure you take what you need. This helps them to remember to cross off the original number and make it one less when regrouping.

The Steps to This Algorithm

1. Align your numbers by place from right to left, lining up digits with ...

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